College of Food Science and Nutritional Engineering , China Agricultural University , 17 Qinghua Donglu Road , Beijing 100083 , P. R. China.
J Agric Food Chem. 2019 Mar 13;67(10):2801-2810. doi: 10.1021/acs.jafc.9b00087. Epub 2019 Feb 27.
The esterified fraction of jujube ( Ziziphus jujuba Mill.) peel extract showed strong antifungal activity on Alternaria alternata. p-Coumaric acid (pCA) was found to be the most predominant individual phenolic acid that was correlated highly with the antifungal activity of the esterified fraction. Thus, effects of postharvest treatments with pCA and its simplest esterified derivative methyl p-coumarate (MeCA) against black spot rot on jujube fruit caused by A. alternata were investigated. pCA and MeCA strongly suppressed in vitro growth of the fungus and significantly reduced postharvest Alternaria rot on fresh jujubes. Biochemical and transcriptional analysis revealed that pCA and MeCA regulated the expression of some genes encoding antioxidant enzymes and their enzymatic activities, enhanced the phenylpropanoid pathway metabolism, and activated the expression of genes encoding pathogenesis-related proteins. These results suggested that, apart from its direct antifungal activity, pCA and MeCA induced defense responses in jujube fruit against postharvest Alternaria rot.
枣果皮提取物的酯化部分对链格孢菌表现出很强的抗真菌活性。研究发现，对香豆酸（pCA）是最主要的酚酸单体，与酯化部分的抗真菌活性高度相关。因此，研究了 pCA 及其最简单的酯化衍生物甲基对香豆酸甲酯（MeCA）对枣果实由链格孢菌引起的黑斑病的采后处理效果。pCA 和 MeCA 强烈抑制了真菌的体外生长，并显著减少了新鲜枣上的采后链格孢菌腐烂。生化和转录分析表明，pCA 和 MeCA 调节了一些编码抗氧化酶及其酶活性的基因的表达，增强了苯丙烷代谢途径，并激活了与病程相关蛋白编码基因的表达。这些结果表明，除了直接的抗真菌活性外，pCA 和 MeCA 还诱导了枣果实对采后链格孢菌腐烂的防御反应。
